Most two-cycle internal combustion engines require that the user mix two-cycle engine lubricant or oil with the engine fuel or gasoline in the proper proportions, such as, five ounces of engine lubricant per one gallon of gasoline. The mixing of the engine lubricant and fuel must occur prior to refueling the engine.
If the proper ratio of engine lubricant per gasoline is not achieved, and the engine is refueled with the inappropriate mixture, problems with the engine's operation, performance, and efficiency will occur. Over an extended period of time, an improper lubricant to fuel ratio will affect the engine's performance and may induce a series of mechanical problems including engine stalling, rough idle, carbon build-up on spark plugs, inefficient fuel consumption, internal carbon build-up, and premature engine wear.
Prior U.S. Patents have the addressed the mixing of fuel and engine additives.
For example, U.S. Pat. No. 4,286,632 issued to Abel discloses a fuel and oil mixing device that has a separate oil reservoir from the fuel tank and a solenoid actuated valve and pump to mix the fuel and oil together.
U.S. Pat. No. 4,594,971 issued to Borst discloses a variable fuel/oil ratio pump for a two-stroke internal combustion engine. The device emits pressure pulses to communicate with the engine.
U.S. Pat. No. 4,846,118 issued to Slattery et al. discloses a duel fuel pump and oil-fuel mixing valve system for use on a boat engine.
U.S. Pat. No. 4,955,943 issued to Hensel et al, discloses a metering pump controlled oil injection system for two-cycle engines that utilizes a fuel supply control and metering pump to deliver oil to the fuel supply system.
U.S. Pat. No. 4,971,118 issued to Cluff discloses a fuel additive mixing system that uses a metering valve for metering the flow of oil, or other mixture, into the flow of fuel as the fuel tank is being filled with a nozzle.
And U.S. Pat. No. 4,069,835 issued to Stadler discloses a fuel and lubricant mixer that operates by being placed directly onto the engine fuel tank and then the dispenser accepts a fuel hose nozzle. However, the mixer requires that the user attach the mixer to the fuel tank, refuel the engine, and then detach the mixer from the tank. Many two-cycle engines are not refuelled with a fuel nozzle, for example, lawn mowers are typically refueled by a fuel container, which may not have a spout long enough or rigid enough to activate the mixer disclosed in the patent.
All of the patents described above require either that the device be attached directly to the engine fuel tank, fuel nozzle, or that the device be integrated into the engine fuel system. None of the prior art patents provide a simple solution for consistently mixing the proper ratio of engine lubricant and engine fuel.
What is needed is a lubricant dispensing device that is operated separately from the engine gas tank and fuel nozzle and that consistently provides the proper mixing ratio of engine lubricant versus engine fuel.